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    <title>ShellCheck: SC2109 – Instead of `[ a || b ]`, use `[ a ] || [ b ]`.</title>
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    <h1>SC2109 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2109">See this page on GitHub</a>
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    <h2 id="instead-of--a--b--use--a----b-">Instead of
<code>[ a || b ]</code>, use <code>[ a ] || [ b ]</code>.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2109.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="bu">[</span> <span class="st">&quot;</span><span class="va">$1</span><span class="st">&quot;</span> <span class="ot">=</span> <span class="st">&quot;-v&quot;</span> <span class="er">||</span> <span class="st">&quot;</span><span class="va">$1</span><span class="st">&quot;</span> = <span class="st">&quot;-help&quot;</span> ]</span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2109.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="bu">[</span> <span class="st">&quot;</span><span class="va">$1</span><span class="st">&quot;</span> <span class="ot">=</span> <span class="st">&quot;-v&quot;</span> <span class="bu">]</span> <span class="kw">||</span> <span class="bu">[</span> <span class="st">&quot;</span><span class="va">$1</span><span class="st">&quot;</span> <span class="ot">=</span> <span class="st">&quot;-help&quot;</span> <span class="bu">]</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p><code>||</code> cannot be used in a <code>[ .. ]</code> test
expression. Instead, make two <code>[ .. ]</code> expressions and put
the <code>||</code> between them.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None.</p>
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